The Cause is Sufficient
by Makalaure
Summary: "On the contrary," Spock said, "my father said he found you very Vulcan." S/Mc.


Note: In case it was not clear: the 'S/Mc' in the summary is an indication of slash.

The Cause is Sufficient

McCoy was still in his uniform and his hair was askew, as if he had been working since early morning and had not had a chance to even finger-comb it. Spock felt a prick of guilt for seeking his company. "May I come in?" He almost wished McCoy would say no, so that he would not have to play host at this hour.

"Please." McCoy, never one to refuse a friend, stepped aside. "You need anything?"

"Negative," Spock said, and breezed in.

He and McCoy had ceased to dance around each other as they had during their five-year mission. Death can be a sound arbiter of repression, and excuses to speak to each other had been discarded. (In honesty, they had never needed excuses, but they blamed them anyway. You are being illogical. You are being cold. Jim is behaving unusually. So on. Pale, limp things that Jim saw through almost immediately but Spock and McCoy did not.)

As McCoy rustled up two cups of green tea without being asked, Spock sat on McCoy's sofa. The faux leather squawked as he did so, and he bit back a grimace. They – the old Enterprise bridge crew – were all senior officers now, close to retiring, and received hefty stipends. It was luxurious, but strange; they had always made do with discomfort and impossible workloads, had been satisfied that way. This sedate, near-aristocratic lifestyle disquieted Spock even as he understood the need to make room for new generations in Starfleet.

McCoy handed a cup to Spock, who nodded his thanks and took a sip. The tea was perfectly brewed, with just a shade of bitterness, the way Spock liked it. One would perhaps not have expected someone as fond of brandy as McCoy to possess knowledge of an art as refined as preparing tea. But McCoy had always been a man of dualities.

The silence was not awkward – it never was between them – but Spock still wished to speak, to take a few more tottering steps in their changed friendship. "My father said he was intrigued that I gave you my katra. Apparently, he barreled into Jim's house and initiated a mind-meld with him. He was certain I had entrusted him with it."

It would have been amusing had the situation not been so dire. Never before had Spock been pushed so brutally to choose between these two men, whom he loved with equal fervour. Both were compatible with him, and Jim would have been a good choice, but McCoy was more ideal. Someone was needed to get Spock's katra back to Vulcan. Obtain a ship. Pilot it. Navigate hostile species. McCoy would not have been suited to that task, and Jim would have been incapacitated.

Nevertheless, his actions had brought both of his friends harm. He had always had Jim or McCoy to save him from that. Jim had lost his son (a thing that Spock could not forgive himself for; he barely resisted hating himself for it), and McCoy...Spock had not even known the repercussions of transferring a katra to a human – McCoy could have died on the spot. He could have lost his mind. Even as Spock put his fingers on McCoy's psi-points, he had remembered, with some shame, that McCoy was the type of person to immediately forgive you if you hurt him. Spock knew; he'd had his hands around McCoy's throat before. The memory had almost been enough to make him stop the transfer.

And now, something had changed between him and McCoy. Sharing a mind and body was overwhelmingly intimate. More than coitus. More than marriage. They were bonded in a way they could never be with anyone else, in a way that no two other people were – a Vulcan entrusting his katra to a human had been unheard of.

Even now, his mind sometimes resounded with faint echoes of unfamiliar memories: sunlight over plains. A little girl with curly hair. An old man lying still and pale in a hospital bed. They slipped in and out of his consciousness, unbidden, like waves over sand. He wondered if McCoy experienced something similar.

McCoy shuddered at the mention of the meld and put his tea on the desk. Understandable, given his unpleasant ( _Traumatic_ , Spock corrected himself. _Use the word_ ) experiences with those. "So I heard. Must've been appalled that you'd given your katra to a guy who's opposite of everything a Vulcan should be." He wiped his gnarled hands on his trousers, though they seemed clean.

"On the contrary," Spock said, "my father said he found you very Vulcan." Spock had been surprised at Sarek's insight. His father was not renowned for his judgement of character. _The EQ of a Denebian slime devil_ , Michael used to say with an ironic smile.

McCoy's eyebrow went right up. "I see where you get that sarcasm."

"He was not being sarcastic."

McCoy rubbed his temple and then ran his fingers through his hair. It had grown downy with age, and was more silver than brown. It gave him a softer look, eased the glint of his still sharp, bright gaze. Spock was thrown, momentarily, by the reminder of McCoy's whittling lifespan. "I'm afraid I don't get the logic behind that statement," McCoy said.

Spock sipped his tea to hide his unease. "You are indeed illogical, and passionate even by human standards."

McCoy scoffed. Still the same man, all these years later.

"You also display several characteristics held in high regard by Vulcans."

"Lord spare me," said McCoy with a grin, leaning back against his desk and crossing his knees. "This oughta be good."

Spock inclined his head. " _The needs of the many outweigh the needs of the few_."

McCoy stilled, his smile fading. "Now, you know I don't subscribe to that hogwash," he said. He was angry now. So characteristically McCoy. Spock thought, amused, _I am terribly fond of this man_. Of all the humans he had met, he had been the least likely to develop any type of bond with Leonard McCoy. At first, his Vulcan half had rebelled, insisted that the doctor was nothing but an unrelenting nuisance – but it quickly became clear that they shared a unique type of kinship. To deny it would have been illogical at best and folly at worst.

"I believe, Doctor," said Spock, "that you do."

"Now wait just a darn –"

"Minara II."

McCoy purses his lips. "What?"

"The Onlies. The mirror universe. Platonius."

"What are you on about?"

"You sacrificed your safety – or tried to – on every one of these occasions, for the sake of the crew. I could name more instances. Clearly, you believed that the value of our lives outweighed yours."

"That's different!"

Spock pinned him with a look. "Is it?"

"Spock." McCoy shook his head, tugged his collar. He reached for his cup and took a sip. "Wouldn't you let a few die for the sake of the many?"

Spock barely resisted the urge to roll his eyes. For all McCoy's medical genius, he could be astoundingly obtuse. Country human, indeed, he thought, a little unkindly. "Have I ever done such a thing?"

"On the Galileo mission – "

"I said I had the right to choose whom to leave behind, which is true. However, I never said I had any intention of doing so."

McCoy blushed and looked at his boots.

"And do not pretend," continued Spock, "that you would not have done as I had in the reactor chamber."

The anger was back in McCoy's face, but it was tainted by something else, heavy and prickly and dark. Something like grief.

"You were held back by the fact that you were needed as a medic onboard. However, if you had not been," and here Spock looked McCoy in the eye, his voice sharp, "I have no doubt that it is your body we would have found there." It was difficult to say. The image it conjured – of McCoy slumped against a wall, his human body too weak to even stagger up, to bid a final farewell – brought a throbbing, dark ache to his chest. Unlike Spock, McCoy would not have had a second chance at life.

McCoy ran his thumb over the edge of his desk. He did not look at Spock. "It would have been my job," he said quietly.

 _It should have been me,_ was what Spock heard. McCoy always had a way of getting under his skin. It was his turn to grow angry. Years ago, he might have suppressed the reaction; now, he was more at peace with his human heritage, surrendered to it as he would to a natural force, as fields did to rain. This was in no small part thanks to McCoy, but Spock was not feeling charitable towards him at the moment. "And that," he said tightly, "is a martyr complex, not a sign of duty."

It was a fine line.

Spock had always been relentless. He was familiar with the term, had known it since he was twelve and studying till the third hour of the morning while other children his age slept. It involved pushing to breaking point, and then pushing harder, because he did not break. He knew people meant it as a compliment when they called him a genius, but to him it was an affront – it implied he did not work himself raw for what he achieved.

He had found in the good doctor, to his unspoken delight, a similar steeliness with himself, an absolute refusal to accept anything less than stupefying brilliance.

Looking at things from another point of view was always uncomfortable, and they tried each other, pushed each other, even. It was exhilarating. Spock thought they understood each other. He had assumed that, if it came down to McCoy sacrificing himself, he would be regretful, but allow it. They were the type of people to die in the line of duty. He accepted that.

And then they beamed down to a planet full of lost children who died once they reached adolescence. Looking at McCoy splayed on the ground had felt like a kick to the solar plexus, and he had held McCoy's hands uselessly and wondered, if he prayed, whether McCoy would live, because there was nothing he could do and his human half only wanted to _scream_.

"And how do you know the difference?" retorted McCoy, breaking Spock's thoughts. "I took an oath. It's no different than any of your tenets." He took a shuddering breath. "You're as bad as I am."

"Then you admit we are not so different."

McCoy glared. "Anyhow, that's just one thing, and it's dubious at best."

"There is another. _There is no offence where none is taken_."

At that, McCoy barked a startled laugh. "You've got to be joking. Spock, we offend each other all the time."

"No," said Spock, "we insult each other all the time, but we do not often take offence."

McCoy scoffed softly. "Some of the things we've said to each other...perhaps we should have."

"Be that as it may, we did not. Or at least, not for long. We have always returned to each other, as friends." _As more_ , he wanted to say. He had been – and at times still is – confused by what they had. It was not easy, languid, fluid, like his and Jim's. It was tempestuous, terribly affectionate, ruthlessly supportive. And it was all, somehow, akin to a secret. Spock had gone to him, on several occasions, in times when he was hurt, or bitter, or puzzled. During the Babel conference, flushed with embarrassment and shame, he had requested McCoy to stand close by his side. McCoy had, solid as an anchor, quiet as midwinter. Yes, it was a quiet friendship, for all their bickering. Small wonder Sarek had known nothing of them.

McCoy said, "I thought this was about me?"

"It is about you and Vulcans, and so about both of us."

A grunt. "Any other of your teachings I'm supposed to be aware of?"

Spock raised his chin, surprised himself with his own earnestness. He only just managed to not hold out his hand, his index and middle finger extended. " _We have differences. May we, together, become greater than the sum of both of us_."

McCoy opened his mouth as if to argue and then shut it, and Spock allowed himself a moment of smugness to have successfully rendered McCoy mute. Then McCoy cleared his throat and said, "I'm tired. Why am I even talking to you?"

"You have a masochistic desire to lose arguments."

"I think I liked you better before you died."

"I think you admitted you liked me." Perhaps, Spock thought, they did still dance sometimes.

"All right, you," said McCoy, wagging a finger, "you need to shut up."

Spock was about to retort, but could not fight a yawn, and his eyes watered. "Much as I am loath to give you satisfaction for any reason, I will leave you to your quarters." When he stood up, his knees cracked.

McCoy looked at him with sympathy, and something like tentative hope in his eyes. "You're free to stay here," he said, soft and heartfelt.

Spock almost refused on impulse. Almost.

Dancing was a tiring activity.

"Thank you, Doctor," he said. "I will stay."

He removed his shoes and jacket while McCoy rustled about in the washroom. McCoy emerged smelling of toothpaste and soap and carrying a fresh set of standard-issue nightclothes. They would have been a couple of sizes large on McCoy, and just about fitted Spock. (He remembered when they were roughly of the same build.) After he slid into the cool bed, he whispered, "You are too thin." At an age when he should have put on weight, like Jim and even Spock, McCoy had only lost it, and he had been slight to begin with. It was painful, at times, to look at him, to see the shapes of the bones beneath his face.

McCoy lay down beside him, fluffing his pillow before resting his head on it. "Stop worrying."

Spock settled a hand on his shoulder. He was afraid if he pressed down slightly, he would break it.

"Spock," McCoy chided gently, and Spock kissed him, carding his hand through feathery hair. McCoy used to smell of sickbay, of antiseptic and rubber gloves and sterilised steel. That scent was fainter now, almost gone; McCoy did not treat people as often as before; he spent most of his time supervising and instructing. Spock put his nose against McCoy's neck, breathed in.

"Are we going to talk about this?" McCoy said, barely audible.

Spock toyed with a lock of silver hair. "Tomorrow." They were both sleepy now. McCoy nodded, and then sighed, and Spock pressed their lips together again.

Yes, tomorrow they would talk.

-end-


End file.
